Loud speaker



Mmh s, 192s; 1,661,541

y u, H. MCNEIL ET Ax.

LOUD SPEAKER Filed @1.15. 192'? gWntoz akamu Patented Mar. 6, 1928-`Ull,l1-11nu sra-ras.

iA-'inN'iA olf-Filer..l i

LOUD SPEAKER.

`Application led January 15,` 1927. Serial No.'161',316.

Our invention relates to radio reception and has for its object toprovide a new and elicient loud speaker for radios.

A further object is to provide an economically constructedV loud speakerfor radios which has few parts and is easily and economicallyconstructed and assembled and one in which the parts may all be madewith few operations.

A further object is to provide a radio loud -speaker which willeliminate much of the static now found in most loud speakers and much ofthe vibration from the working parts of the speaker. y y

These objects we accomplish with the device illustrated lin theaccompanying drawings in which similar numerals and letters of referenceindicate like parts throughout the several views and as described in thespecification forming a part of this application and pointed out in theappended claims.

In` the drawings in which we have shown the best and most preferredmanner of building our invention, Figure 1 is a plan view of the loudspeaker. Figure 2 isa plan view of the same with parts removed. Figure 3is a side elevation of the device with the coils removed from theircores. Figure 4 is a. plan view with only the pole pieces shown attachedto the base. Figure is a diagrammatic view of the coils and armatureshowing the way that the armature is suspended and the connection of thearmature with the diaphragm.

In the drawings we have shown the base, in which the diaphragm A Vismounted as B. Two pole pieces 1 and 2 stamped from soft iron are rivetedto the said base B, as shown in Figure 4, with the bolts 3 and 4 shownprotruding therefrom. The said bolts 3 and 4 are passed through the baseB and the pole pieces 1 and 2 and hold the entire assembly together. Anon-conductor plate 5, having holes therethrough to match the bolts, is

" 'then placed on the bolts 3 and 4, with an insulator plate Dsuperimposed thereon, and the free ends of a permanent magnet C areplaced under the said plate 5 and held in .place by screwing the nuts 6down on the bolts 3 and 4, with the ends of the magnet clamped under theends of the plate 5 and on top of the pole pieces 1 and 2. Connectionterminals 7 are secured to the said vinsulator plate D and are adaptedto be connected with theradio set, and are also connected with theelectromagnets E. The said electromagnets E are carried on soft ironcores 8 and 9 which cores are secured on the ends of the pole pieces 1and 2, as shown in Figure The said electromagnets vare connected withthe terminalsi' by the wires 10 and 11. `An armature F is mounted abovethe said electromagnets by being suspended from the non-conductor plate5 by two spaced apart suspension pins 12 and 13, and one end of the saidarmature is tapered to a point and is connected with the diaphragm A bya pin 14.

The operationY of our device is as follows:

When the loud speaker' is assembled and connected with a receiving setit is ready to operate and the pulsations of the incoming electricalcircuits will act upon the electromagnets and will vibrate the armatureF which will, in turn, through the pin 14, transmit the vibrations tothediaphragm A and will reproduce the music, voice or code being sent overthe air or wires.

The suspension of the diaphragm over the electromagnet. cores gives aclear, decided action `to the armature, and transmits that to thediaphragm, thus giving clearer reception. The pole pieces 1 and 2 arestamped out of sheet metal and are identical in form and all of theparts of the entire assembly are easily and cheaply built.

Having thus described our invention we desire to secure by LettersPatent and claim 1. In a loud speaker the combination of a base, havinga diaphragm mounted therein; pole pieces riveted to said base;a perma-`nent magnet superimposed over said pole pieces and held in contacttherewith by bolts; bolts secured in said base and passed through saidpole pieces and on which nuts are provided to hold `the entire assemblytogether; a non-conductor plate` over the ends of said magnet andholding said magnet to said pole pieces by the pressureexerted` by thebolts and nuts thereon and therethrough; cores secured on said polepieces and carrying electromagnets; an armature suspended from saidnon-conductor by spaced apart pins and said armature held directly oversaid electromagnets; and a pin' connecting said armature with saiddiaphragm.V

'2. In a loud speaker the combination of a base; a diaphragm mounted insaid base; pole pieces secured on said base; a permanent magnetsuperimposed over said pole pieces; bolts secured in said base; anonnpuit pins, suspending said armature over 10 conductor plate over theends of said pernmthe said cores and eleetromngnets; :1y pin nent magnetadapted to be drawn down on connecting one end of said armature withsaid magnet by said bolts to hold said magsaid diaphragm; und nuts onsaid bolts to net in fixed relation to said pole pieces and hold theentire nsselnbly'together.

said buse; cores of soft iron secured in the In testimony whereofl wehave :lllixed oni' ends of said pole pieces; eleetromngnetsezusignatures.

ried on said cores; an armature suspended ULRUS H. MCNEIL.

from said non-conductor plate by spaced FRANCIS G. PEARCE.

